Scientists have found that the ant is the first known animal both to process the location of odors and to use that information to create a cognitive map. And for ants, that means their pair of antennae work overtime to recognize and process multiple odors simultaneously. In other words, it seems ants smell in stereo.
Markus Knaden and colleagues from the Max-Planck Institute for Chemical Ecology set up olfactory landmarks near the entrance to a barely visible desert ant nest in Tunisia. After the ants searched for food and returned, the researchers moved the odor markers to a remote location without a nest entrance. Sure enough, the ants located the area and searched for the entrance, despite the lack of visual cues.
Steck, K., Knaden, M., & Hansson, B. (2010). Do desert ants smell the scenery in stereo? Animal Behaviour DOI: 10.1016/j.anbehav.2010.01.011